How to test hard drive speed?

I just install a second hard drive this. The website said Rotational Speed : 7200 rpm. and Data Transfer Rates : 300 MB/s.
When I check the sticker on the hard drive. It said Data Transfer Rates : 150MB/s. And Nowhere mention about Rotational Speed.
Can you some recommend a free software to check this information?
Thank you.

That does not have to be bad. It depends from model you bought. You have WD Caviar Blue (Performance and reliability -average performance ), WD Caviar Green (Cool, quiet, eco-friendly - low performance) ,WD Caviar Black (Maximum performance - max performance). Check which one is your model, and you'll know if you need to be worried.